Definition of gabbro:
- "The Economic Aspect of Geology", C. K. Leith.
- "The Elements of Geology", William Harmon Norton.
The rock which prevails in this region consists mainly of gabbro, which in the interior forms several isolated, black, plateau- formed hills, 100 to 150 metres high, between which an even, grassy, but treeless plain extends.- "The Voyage of the Vega round Asia and Europe, Volume I and Volume II", A.E. Nordenskieold.